The present inventive concept herein relates to a power supply circuit of a semiconductor integrated circuit (IC) and an operation method thereof, and more particularly, to a current reference circuit and a semiconductor IC including the same.
Current reference circuits may be used in semiconductor ICs to generate a reference current having the characteristic of a proportional to absolute temperature (PTAT) current where the reference current increases in proportion to a temperature change. The reference current may be used as a bias current by circuits in the semiconductor IC. However, when the reference current increases in proportion to a temperature, operating currents of all circuits using the reference current as a bias current increase in proportion to an increase in a temperature. If the number of circuits using the reference current increases, consumption power increases to more than a designed value at a high temperature.